var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var usersRouter = require('./routes/users');
var article = require('./routes/article');
var backgroudTask = require('./backgroud_task');

var app = express();

app.all("*", function (req, res, next) {
      //设置允许跨域的域名，*代表允许任意域名跨域
      res.header("Access-Control-Allow-Origin", "*");
      //允许的header类型
      res.header("Access-Control-Allow-Headers", "content-type");
      //跨域允许的请求方式 
      res.header("Access-Control-Allow-Methods", "DELETE,PUT,POST,GET,OPTIONS");
      if (req.method.toLowerCase() == 'options')
        res.sendStatus(200); //让options尝试请求快速结束
      else
        next();
    }
)

app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/users', usersRouter);
app.use('/article/v1', article);

app.use(function(req, res, next) {
  next(createError(404));
});

app.use(function(err, req, res, next) {
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  res.status(err.status || 500);
  res.render('error');
});

app.startBackgroundTask = function() {
    backgroudTask.start();
}

module.exports = app;
